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It shouldn’t come as a surprise that psychological studies on “priming” may have overstated the effects. It sounds plausible that thinking about words associated with old age might make someone walk slower afterwards for example, but as has been shown for many effects like this, they are nearly impossible to replicate.

Now Ulrich Schimmack, Moritz Heene, and Kamini Kesavan have dug a bit deeper into this, in a post at Replicability-Index titled “Reconstruction of a Train Wreck: How Priming Research Went off the Rails”. They analysed all studies cited in Chapter 4 of Daniel Kahneman’s book “Thinking Fast and Slow”. I’m also a big fan of the book, so this was interesting to read.

I’d recommend everyone with even a passing interest on these things to go and read the whole fascinating post. I’ll just note the authors’ conclusion: “…priming research is a train wreck and readers […] should not consider the presented studies as scientific evidence that subtle cues in their environment can have strong effects on their behavior outside their awareness.”

The irony is pointed out by Kahneman himself in his response: “there is a special irony in my mistake because the first paper that Amos Tversky and I published was about the belief in the “law of small numbers,” which allows researchers to trust the results of underpowered studies with unreasonably small samples.”

Two recent reads on similar themes. Paul Ormerod has written a few interesting books about economics and networks already (starting with The Death of Economics), and his latest from a couple of years ago continues on similar themes. Alex Pentland’s book from last year is also concerned with networks. Both books also follow a similar structure: a bunch of interesting studies, examples, and stories to begin with, followed by a more general discussion of “what ought to be done” at the end.

Where they differ is in their confidence. Ormerod talks a lot about the unpredictable nature of human behaviour, and is (rightly, I think) skeptical of any central government being able to manage things as complex as a national economy. Pentland, on the other hand, is convinced that with enough big data and some clever mining of it, any social problem is just waiting to be solved. Absolutely, the methods and findings he presents in the first half of his book are very interesting, but I couldn’t help thinking that he is more or less dismissing almost everything ever done in any of the social sciences (plus psychology and a few other fields as well). For example, he ignores more or less all of economics since Adam Smith: I’m no great fan of much of economic theory either, but there is still much insight there to be found. And it would be easy to pick holes in his logical jumps from a handful of studies to wide-reaching conclusions about human nature and behaviour. Plus all the big data critiques still apply.

I finally got round to reading Ben Goldacre’s book Bad Pharma. I’m not going to go into too much detail about the book, but if you have even a passing interest in medicine, public health and the costs of providing it, or your own health, I would highly recommend that you read it too. These are some of the random thoughts it raised in me.

First, you only had to know medical students at university, and see what freebies they got from drug companies, to know that something was up. And I’ve long been interested in publication bias. So I was already at least aware of most of the issues, but the book is still quite a catalogue of all kinds of rogue behaviours by many actors. Pharma companies misbehave of course, but so do drugs regulators around the world (I was probably most surprised by just how useless – and even worse – they are), professional bodies, journals and their editors, patient groups, doctors and academics. There is a lot of money going around, and therefore corruption both big and small, explicit and implicit. Nobody comes out too well in this story.

Second, since my backgroud is in banking, I couldn’t help making comparisons. Bankers misbehave too, no doubt about it. Both industries are heavily regulated, but the regulators have in both instances been fairly comprehensively captured by industry interests. In bankers’ defense, when they fiddle LIBOR rates, some other financial company may lose a few million dollars, but when drug developers intentionally hide adverse data about their products, thousands of people will die. So why is there so much less outcry about pharma? It is probably more complex to understand publication bias than lying about benchmark rates. And the deaths are isolated and hidden from view, whereas the financial crisis was very much visible on every high street.

And finally. In passing, Goldacre says something along the lines of “just because there are issues with medicine, it doesn’t mean that alternative medicine works”. Sure. But the opposite works as well: just because homeopathy doesn’t work, it doesn’t mean that (“traditional” or whatever you want to call it) medicine necessarily works any better. To be clear, I don’t think there’s any physical way that homeopathy works. But you can also be prescribed medicines by your GP that are not much better than placebo, if at all. So when a lazy skeptic rants about homeopathy and “the scientific method”, they should always be reminded that there is science and then there’s cargo cult science. Medicine is beginning to look more and more like a cargo cult than the real thing – there are journals, trials, complex statistics etc, but if it’s all based on smoke and mirrors then what do you really have that you can rely on? My attitude is to pay more attention to studies of how science is actually done: its history and sociology, and not just what scientists say in after-dinner speeches. The reality is always much more messy than “hypothesis, test, replication”.